Smoking on initial start-up
 

My 2004 Tahoe is smoking on initial start-up. It seems to oil smoke, but it is not constant like a broken ring. After about a minute, the smoking clears up. Coule it be the following:

• A broken ring
• A sticking injector causes excessive fuel after shutdown
• A blown head gasket causing oil to seep into the chamber during shutdown
• A broken valve stem seal

What should I check first???
Any ideas?
Thanks

Most likely worn stem seals. Oil leaks past them when engine is not running and burns off when started.

X2 on valve seals

Might help if you said how miles are on it.........